sources say the package contained handwritten papers that holmes addressed to one of his instructors who is also a psychiatrist. in the documents, they say holmes talked about shooting people and even included crude drawings ever a gunman and his victims. >> came here, like they have a super power. >> reporter: video shows holmes before the shooting, giving a presentation at a science camp. aurora officials are under a strict gag order, unable to share information about holmes or the case, but benchers like retired police detective sherman says the new evidence could provide valuable information. >> the fbi has capable science people. and what they're able to do is look at the writing and discuss and see if it was the ramblings of somebody. are they coherent? what is their background? their education? >> reporter: after looking at holmes' apartment for days, investigators turned the apartment building back over to residents last night. holmeps -- holmes' residence, which was once stringed with a bunch of booby traps, is now empty. >> the police and fbi and atf already took that stuff